Determination of rock types by spectral scanning

A method of mining comprising:

• producing rock type classifying data for a rock body by:
• scanning a mine bench face with a spectral sensor to obtain spectral data from the rock body at the bench face, said data comprising multiple spectra obtained from scanned regions of the rock body surface,
• determining, by a processing system, for differing spectra within the multiple spectra a plurality of spectral ratios as indicators of differing rock types, the spectral ratios being derived from a comparison of the spectral data at different specific wavelength bands associated with diagnostic absorption features of the differing rock types, said comparison comprising dividing a sum of reflectance in a first wavelength band by a sum of reflectance in a second wavelength band,
• comparing, by the processing system, the spectral ratios to a threshold ratio, the spectral ratios used for the comparing are based on the dividing of the sum of reflectance in the first wavelength band by the sum of reflectance in the second wavelength band, the threshold ratio predetermined to define spectral ratios indicative of an absorption feature associated with edge anomalies of at least one edge of a portion of the rock body, and
• in response to a determination, based on the comparing, that the spectral ratios do not indicate an absorption feature associated with edge anomalies, classifying, by the processing system, one or more rock types present at the rock body surface based on the spectral ratios and generating rock type classifying data for the rock body based on the identifying.

A method for removing material from a rock body comprising:

• producing rock type classifying data for the rock body by:
• obtaining, at a processor for processing images, spectral data from a spectral measurement of a surface region of the rock body,
• determining, by the processor, a first spectral ratio between two wavelength bands of the spectral data,
• comparing, by the processor, the first spectral ratio to a threshold ratio, the threshold ratio predetermined to define spectral ratios that indicate an absorption feature associated with edge anomalies of at least one edge of a portion of the rock body,
• in response to a determination, based on the comparing, that the first spectral ratio does not indicate an absorption feature associated with edge anomalies, determining, by the processor, a further spectral ratio between two further wavelength bands of the spectral data,
• comparing, by the processor, the further spectral ratio with a corresponding diagnostic criterion to assess whether the surface region comprises a first rock type associated with the further spectral ratio and diagnostic criterion, and
• classifying, by the processor, the first rock type present at the rock body surface based on the assessment of the further spectral ratio and diagnostic criterion and generating rock type classifying data for the rock body based on the classifying;
• and
• wherein the spectral measurement comprises images at discrete and narrow bands, including the wavelength bands for the first spectral ratio and the further spectral ratio.